I'm running a Hybrid Turbo on my 13B Cosmo and in planning for upgrades, I'; considering doing a half bridge port and later upgrading the turbo to a GT35r or something in that range. I want this car to be very street drivable and I know the downside of vacuum leaks.



In trying to further understand how the rotary works and responds to modifications, I have questions:



Is Exhaust Backpressure essentially the inverse of Intake Vacuum?



Does Exhaust Backpressure preclude or nullify Intake Vacuum?



Does half bridge porting reduce or nullify Intake Vacuum?



Is Intake Vacuum required for stable cruse RPMs?



*If* cruse RPMs' driving stability is reduced because of low vacuum level, what is physically responding (or not responding) to the low vacuum level and is there a remedy to supplement that could increase the vacuum level in order to stabilize cruse RPMs driving stability?